Guard for circular saws.



J. EDMAN.

GUARD FOR CIRCULAR SAWS.

APPLICATIQN FILED FEB- 19. I913.

Patented Apr. 13, 1915.

2 SHEETSSHBET 1.

THE NORRIS PETERS C0,, PHOTG-LITHOH \VASHINGTON. D. C.

J. EDMAN.

GUARD FOR CIRCULAR SAWS.

APPLICATION FILED FEB- 19. ms.

Patemmdl Apr. 13, 1915.

2 SHEETS-SHEET 2.

Fwy. 5

THE NOHNI: r'nlnna U0" PHOTOJJTHO. WASHINGTON. D- C rrns r ar.

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JOHN EDMAN, 0F MINNEAPOLIS, MINNESOTA, ASSIGNOR OF ONE-HALF TO THE FIRM0F WILLIAMSON & MERCHANT, JAMES F. WILLIAMSON AND FRANK D. MERCHANT, OFMINNEAPOLIS, MINNESQTA, COPARTNEBS.

cunnn non CIRCULAR saws.

menace.

Specification of Letters Patent.

Patented Apr. 13, 1915..

Application filed February 19, 1913. Serial No. 749,379.

To all whom it may concern: j

Be it known that I, JOHN EDMAN, a citizen of the United States, residingat Minneapolis, in the county of Hennepin and State of Minnesota, haveinvented certain new and useful Improvements in Guards for CircularSaws; and I do hereby declare the following to be a full, clear, andexact description of the invention, such aswill enable others skilled inthe art to which it appertains to make and use the same. I

My invention has for its object to provide an improved guard especiallyadapted for use in connection with circular saws, but adapted also foruse in connection with rotary cutting heads of various different kindsof wood working machines.

Generally stated, the invention consists of the novel devices andcombinations of de vices hereinafter described and defined in theclaims.

In the accompanying drawings which illustrate the invention, likecharacters indicate like parts throughout the several views.

Referring to the drawings, Figure 1 is a plan view with some partsbroken away showing the improved guard applied over a circular saw; Fig.2 is a side elevation of the parts shown in Fig. 1; Fig. 3 is a verticalsection taken on the line m -0a on Fig. 1;

g and Fig. 4 is a transverse section taken on the line w m* on Fig. 2.

The numeral 1 indicates a work table, the numeral 2 a rotary powerdriven spindle and the numeral 3 an ordinary circular saw, which sawworks upward through a slot in the said work table. The numeral 4inclicates a gage bracket adjustably secured on the work table in thecustomary way, by means of nutequipped bolts 5, or otherwise, andprovided with a working face that is parallel to the plane of the saw 3.

The guard, as preferably constructed, comprises a pair of pivotallyconnected cage segments 6 and laterally spaced side plates 7. The cagesegments 6 are preferably pivotally connected to each other and to asupporting bar 8, by an engaging bolt 9, said cage segments beingpreferably formed at plates 7 and through the flanges of the front cagesegment 6 and serving to pivotally connect the said parts. The rear cagesegment 6 has trunnions 11 that work in longitudinal slots 12 formed inthe rear ends of the said side plates 7. Preferably, also, the sideplates 7 are provided with upwardly extended intermediate portionshaving segmental slots 13 concentric to the axis of the rod 10, and theside flanges of the said front cage segment 6 are formed with trunnions14; that work in the said slots. Preferably, the bolt 10 and thetrunnions 11 and 14: are provided with nuts at their outer ends.

The above described connections permit the cage sections 6 toindependently rise and fall carrying vertically with them the sideplates 7. The side plates 7 and the flanges of the cage segments 6prevent the fingers or hand from being accidentally moved into contactwith the saw or cutter from the sides of the guard.

The free edges of the front and rear cage segment 6 are supported onrollers, the roller 15 in the former being journaled on the rod 10,while the roller 16 in the rear cage seg ment has trunnions directlyournaled in the side flanges of the-said rear cage segment.

The top or body sections of the cage segment 6 are preferably slatted sothat the saw maybe seen by the operator, but to prevent throwing ofsawdust or small particles through the bars of the front cage segment 6,the latter is provided with an auxiliary hinged segment cover 17 in theform of a marginal frame and a wire screen panel.

The supporting bar 8 is preferably made in two sections separated at 8",the sections of the said bar having rigidly secured yokelike hingebrackets 18 and 19 pivotally connected by hinge bolts 20. This jointpermits the entire guard to be moved pivotally and turned upside downinto an inoperative position shown by dotted lines in Fig. 4:.

When the guard is in use, the supporting bar 8 should'be made rigid orstiff and. this may be conveniently done by a lock bolt 21 idly securedon the rear edge of the work (see Figs. 1 and 4) slidably mounted on themain section of the said bar 8, and adapted to be slid so that it willoverlap the other section of the said bar. The main section of the saidbar 8'is slidably mounted, as shown, in a bearing 22 on the adjustablegage bracket 4, and in a bearing pedestal 23 rigtable 1. A set screw 24:appliedto the said bearing pedestal serves to lock the bar 8 againstendwise sliding movements. I

An oblique lifting board or plate 25 is pivotally connected tothe frontends of the side guard plate'7,'as shown, by a rod 26 having nuts 27 atits endswhich, whentightened,

twill rigidly thold the said lifting board in respect to the said'sideplate 7'. This oblique lifting board'25 will serve'to raise the frontedge and roller of the front cage segment 6 when aboard of ordinarythickness is forced endwi'se against the same. Sometimes, however, whena very thick plank-or article is to be sawed or cut, it will benecessary to raise the front portion of theguard, and for this purpose,I preferably provide a lifting cable 28 centrally attached to the rod 26and passed over aguide sheave 29 journaled to a suitable overheadsupport 30.

In Fig. 3, the numeral 31 indicates a plank l or boardwhich is beingsawed and which has raised the sections of the guard and which is, whilebeing sawed, pressed downward by the weight of the guard itself. Whenthe roller 15 is raised, the round rear ends of the side plates 7 willbe forced onto the rear portion of the table 1 and the'rear roller-16will be slightly raised, usually, so

, that it will run on the top of the board being sawed. If the board beextremely thick, it may, in some instances. strike the bottom of theinner side board 7 ,and thereby positively'raise the rear cage segment.When the rear'end of the board passes toward the sawbeyond the frontroller 15, the front cage section 6 will drop, thereby preventing thehand pushing the board. or plank from following the same to the saw; Therear cage section will remain raised and pressed downward on the boarduntil the rear end of the boardis passed beyond the rear roller 16whereupon this'rearcage section'will drop. In this way, the saw orcutting tool is kept caged, positively preventing the handof theoperator from being engaged with the saw or cutting tool, andfurthermore, preventing chips, tool points, or other particles frombeing thrown from the saw or tool.

' The numeral 32 indicates stepped stop ole V vices pivotally connectedto the side plates 7 at the lower extremities of the slots 13. Thesestop devices are frictionally held Where set and are adapted to engagethe nuts on the trunnions 1.4: to variably limit the upward movement ofthe front roller 15. For instance, when inch lumber is being sawed, thestops'can be so set that a two inch plank cannot be forced under theroller 15 and to the saw. 7

There is a tendency for the saw to throw a board forward or backwardunder the front roller 15, and as a simple and efiicient means forpreventing this, and accidents which frequently result therefrom, Iprovide the shaft or rod 10 to which the front roller 15 is rigidlysecured, with a ratchet wheel 33 that is engaged by a gravity-held dog34 pivoted on the adjacent side plate 7. This pawland ratchet devicemight be applied on'the inner side of the casing if desired. i

What I claim is:

1. A guard of the kind described, comprising a pair ofjpivotallyconnected cage 7 sections,extending one in front and one in the rear ofthe tool, and a side plate mounted .for bodily movement with said cagesections and permitting independent vertical movements thereofl 2. A.guard of the kind described, comprising a pair of pivotally connectedcage sections, extending one in front and one in the rear of the tool,and a side plate, pivotally connected to the forward endof said frontcage section, for vertical swinging movement, and connected to said rearcage section for pivotal and sliding movements,

7 with respect thereto.

3. A guard of the kind described, comprising a pair of pivotallyconnected cage sections, extending one in front and one in the rear ofthe tool, and a side plate, pivotally connected to the forward end ofsaid front cage section, for vertical swinging movement, intermediatelyconnected to the rear end portion thereof and to said rear cage section,for pivotal and sliding movements, with respect thereto.

4. A guard of the kind described, comprising a pair of pivotallyconnected cage sections, extending one in front and one in the rear ofthe tool, a side plate, pivotally connected to theforward end of saidfront ment, intermediately connected to the rear In testimony whereof Iafiix my signature end portfion thereclut sad 1to said rear cage inpresence of tWo Witnesses.

section, or pivota an s iding movements,

with respect thereto, and means including a JOHN EDMAN' stepped devicefor variably limiting the sliding movement of said side plate, Withrespect to said front cage section.

Witnesses:

HARRY D. KILGoRE, BERNICE G. WHEELER.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. G.

